This invention relates generally to medical electrical current generators and in particular to iontophoresis devices.
The use of DC current to deliver drugs through the skin of a patient is an old and well known process. Iontophoresis devices typically include a battery and two electrodes coupled to the battery. One electrode typically contains a drug in its ionic form, the other electrode is typically moistened with saline solution or provided with some other ionic conductive medium. For example, such an iontophoresis device is illustrated in U.S. Pat. No. 4,325,367 issued to Tapper. Control of the dosage of the drug provided by such devices has typically been accomplished by control of the current flowing through the electrodes. Various systems for regulating current flow through iontophoresis devices are disclosed in U.S. Pat. Nos. 3,794,910, 4,292,968, 4,301,794, and 4,019,510.